Increasing prevalence of allergic diseases has been noted in most developed and developing countries. Allergic diseases are defined as functional disturbances caused by type I hypersensitivity, i.e., type I immune response mediated by IgE antibodies. The symptoms include pollinosis, bronchial asthma, allergic rhinitis, sinusitis, respiratory distress syndrome, atopic dermatitis and anaphylactic shock. Today, allergic diseases tend to be more severe in civilized societies and have cost a lot of money. Among the people who are suffering from various allergic symptoms, allergic rhinitis is the most common form of allergy. Also, the attack of allergen can sometimes be fatal. According to a statistic data of 1994 conducted by the Pediatrics Department of the Medical College of National Taiwan University, the prevalence rate of allergic rhinitis among students in Taipei city (Taiwan) is over 33%, about 3 times higher than that of asthma (10˜11%). The number of patient is also increasing every year. In particular, patients of young children are on rapid rise. Thus, many researchers are devoting themselves in developing an improved solution to reduce economic and physical burden of the patient from such allergic diseases.
In recent years, with the emerging use of post-transcriptional gene silencing technology, in particular, RNA interference (RNAi), as a tool to knock out expression of specific genes in a variety of organisms (Mello and Conte, “Revealing the world of RNA interference”, (2004) Nature 431, 338-342; and Scherer and Rossi, “Approaches for the sequence-specific knockdown of mRNA”, (2003) Nature Biotechnology, 21, 1457-1465), it is now possible to map protein interactions in cell signaling pathway by systematically silencing functional genes, and thereby providing a new way of developing therapeutics for countless diseases. The present inventors have made extensive clinical researches and experiments and have identified non-coding, short RNA molecules that are capable of suppressing airway inflammation related-gene expression in vitro or in vivo via RNA interference, thus, these identified short RNA molecules are useful as a medicament for treating allergy to alleviate or minimize airway inflammation of a subject.